


Be My Mistake

by zxkhy



Series: "Be My Mistake" - Miya Twins series [1]
Category: Haikyuu!!
Genre: Angst, Angst and Romance, F/M, Fluff and Angst, Haikyuu - Freeform, Teen Angst, haikyuu!! - Freeform, this is a series lol first part
Language: English
Status: Completed
Published: 2020-11-28
Updated: 2020-11-28
Packaged: 2021-03-10 01:54:19
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,681
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27756463
Author URL: https://archiveofourown.org/users/zxkhy/pseuds/zxkhy
Summary: The first chapter of a three-part series.You find out how your boyfriend, Atsumu Miya, really feels about you through a hidden stash of letters baring all his feelings.This chapter is based around the song "Be My Mistake" by The 1975.
Relationships: Miya Atsumu & Miya Osamu, Miya Atsumu & Reader, Miya Atsumu/Reader, Miya Osamu & Reader, Miya Osamu/Reader
Series: "Be My Mistake" - Miya Twins series [1]
Series URL: https://archiveofourown.org/series/2030398
Comments: 14
Kudos: 122





	Be My Mistake

**Author's Note:**

> This was the first ever Miya twins series I wrote, and I fell in love with the characters' relationships here moving forward so I hope you guys love it as much as I do! :)

**Atsumu Miya** is both a blatant perfectionist and a passionate lover.

The former usually relates to Atsumu as a volleyball player. On the court he’s a perfect picture of confidence and seriousness. If there’s one thing you’ve realised over the years is that he has ridiculously high expectations for himself (and his teammates). Although, sometimes that can veer into a bad direction. Rattled even more by a strong hatred of losing.

The latter refers to Atsumu off the court; more specifically, when he’s with you. He always makes sure to rush to you after every game, carry you up in his arms and spin you around; to show you off just the way you like. If he loses, you’re his first go-to once everything ends. He loves hugging you tight, inhaling deeply as the scent of the shampoo lingering in your hair fills his nostrils. And to everyone around you, the two of you are the “it” couple — the one everyone is envious of.

But that’s not the case. Not _really_.

Because beneath his actions lies a different meaning. Atsumu loves you. He really does. But just never as much as you love him, and probably not in the way he wishes it to be. How can he _not_ love you? All you’ve ever done is try to better his life, even if that meant at the expense of your own. He loves that you’re so genuine; so earnest. You only want the best for him, and he can tell it’s real. But something’s bugging him. It always has.

And you know it, too.

You notice it, even in the small instances. And today, you’re finally about to find out why.

•❅──────── ✧❅✦❅✧────────❅•

You fumble for the keys to your shared apartment, several shopping bags in tow. You’ve spent the past hour in the shopping mall nearby browsing for decorative material to adorn your shared bedroom with.

It’s Atsumu’s birthday and you planned for him to get back home after training to a fully-decorated bedroom, filled with balloons and flower petals on the bed; maybe have a little steamy session before you both shower together and get ready for dinner at the restaurant you’ve handpicked with Osamu’s help. (It has _the_ best fatty tuna in the city and you know how much he loves a good fatty tuna.)

You have the whole day planned out, all nice and neat in your day planner. You thumb over the page once more after setting the decorations down on the coffee table.

_Yep, everything seems good. It should all go by without a hitch._

Atsumu has training, so you estimate he’d be back around 5pm. Which means you have a whole seven hours to yourself, just to get everything here all nice and pretty. You even printed out several photos of you two together, just to make an explosion box for him. He’d seen it online a couple of times, and you noted how he said it’d be cool to have one of those. Well now, you’re going to make one for him.

The next two hours are spent on breakfast and making the base of the box, before you decide to take a break by decorating the room. _Just the balloons and the rose petals, easy peasy,_ you think to yourself, bringing them in and visualising just how to arrange them.

So you spend the next half hour tiptoeing on the bed, trying to tie photos onto each helium balloon, the sounds of the bed frame creaking drowned out by the obnoxiously loud music blasting over the bluetooth speakers. Once that part of the decorating is done, you settle yourself on the floor, attempting to start on the explosion box. But your clumsy fingers let slip of one of the photos, letting it fly under the bed frame.

You groan at your own clumsiness. But it was a blessing in disguise, because that’s how you find out that there’s a certain section of the bedframe that’s hollow. You knock against it just to confirm; and the sound asserts it. You tug on it a little harder and remove part of the frame, revealing a small section of space, occupied by just a smaller article: a red box.

Brows furrowed and curiosity piqued, you grab it. It must be Atsumu’s. And even though you know you shouldn’t, you can’t help yourself. He’s been acting so weird lately that it’s getting harder to shake off. Maybe whatever’s in here is the reason. You half-hope for it to be some sort of present for you, some big surprise. But the other logical half of you is snickering at yourself.

How can you be so pathetically hopeful?

Turns out that voice is right. Because inside the box is a collection of letters, with an all-too-familiar name on each one, written in his handwriting. It’s all made out to one person.

And that person isn’t you.

But you recognise the name, how can you not? It’s Atsumu’s ex-girlfriend, the one he tried so hard to get over (did he even really get over her?), the one he dated before you. She’s beautiful too, you’ve seen her a few times. And despite knowing you shouldn’t, you grab at the earliest one (thankfully he dated each one). To your dismay, it was _after_ you guys got together.

•❅──────── ✧❅✦❅✧────────❅•

✎ _she bought me those jeans, the ones you like  
_❝Hey, you changed your number didn’t you? I dunno what your new one is. I would ask… but I think you changed it for a reason, right?

Do you still remember us? ‘Cause I do. Sometimes when I’m on a date I catch myself slippin’, catch myself almost calling her ‘ _princess_ ’. I can’t call her that. You told me never to call anyone but you that. And I know we ain’t together anymore, but I can’t help it.

I’m only here now ‘cause… I hate how you two are so alike. Remember those jeans you said would look so damn good on me? She got it for me as a present. I didn’t even tell her I wanted it. She just… happened to. And it’s not like you fuckin’ care or anything… but I can’t bring myself to wear ‘em. If I do I’ll just keep thinking of you. And when I think of you…❞

He must’ve ended it there. You don’t see anything else written after that.

You swallow the lump in your throat. You always wondered why your boyfriend didn’t want to wear your gift. His reasons were that he wanted to save it for a special occasion. You scoff, remembering how he didn’t wear it even during your birthday a few months ago.

Now you know why.

Lips quivering and fingers trembling, you slowly make your way to the shared closet, socks silent against the hardwood floors. You know exactly where he stashes your gift; on the floor against the corner of the cupboard. You take it out, vacant eyes eyeing it from top to bottom. Atsumu would look really good in those. You — _and her_ — are right.

Guess you _are_ pretty alike. In one sense, or two now. Frustrated, you fling it onto the mattress before grabbing at the next letter.

•❅──────── ✧❅✦❅✧────────❅•

✎ _i don’t want a hug, i just wanna sleep  
the smell of your hair reminds me of her feet  
_❝I hate that you’re stuck in my fucking head. I can’t even go back to bed because I’ll feel so guilty, you know that? Every time we sleep together I feel so guilty. She loves to cuddle. And I don’t mind it, really, I love cuddling her, she’s so cute in my arms, you know? But I fucking ruin it with my stupid thoughts.

Every time I cuddle with her I just can’t get over the fact that her hair feels so different against my skin. I can’t get over the fact that her breathing and yours don’t fit the same rhythm. I can’t get over the fact that the shampoo doesn’t smell the same, or the way her hand feels round my waist just ain’t right. I hate how it’s not… you.

This must be why you called me a horrible person, huh?❞

The tears are already escaping the corners of your eyes, creating tracks down your cheeks. Is that why you were never in his arms for long? You could always feel when he slowly pulled away, trying his best not to wake you. But he always failed. You’re a fairly light sleeper. You tried asking if he didn’t like cuddling more than on one occasion, but he was adamant he liked it.

Just not with you.

Now you know.

Even when you are nothing like her, he can only seem to think of her.

•❅──────── ✧❅✦❅✧────────❅•

✎ _don’t wait outside my hotel room, just wait ’til i give you a sign, ‘cause i get lonesome sometimes  
_❝Okay okay, I got a confession to make. I can’t keep this in. And the only person I really wanna talk to ‘bout this is you. But y’know… Anyway!

So, my confession: I fucked her the same night we broke up. I was just so pissed and I wanted to forget and… she’s always been there for me, you know? She’s so beautiful, and always had my back, been the perfect friend. She’s one of my _best_ friends, actually… but we crossed a line that night… and I just couldn’t bring myself to step back.

I knew she kinda had a thing for me, and maybe I was just being a dick, maybe I was justifying it in my head as ‘when one door closes another one opens’. Thing is, you may have walked away, but I sure as hell didn’t close that door. And I know you probably ain’t ever gonna walk back, so why do I find myself waiting?

No matter how perfect she is, how amazingly talented I find her… why do I feel something missing? When I feel the need to back away, she just somehow goes and makes me feel so happy in the moment that I just can’t. I know what you’d say if you saw this right now: pathetic. Right?❞

The more you read the more you feel like a hurricane has plowed through your heart. The destruction is absolute, your entire being tattered and torn apart. And now maybe you see why some people are addicted to the pain.

Curiosity.

You know the more you see the more you’ll hurt, but your fingers reach for the next letter anyway.

•❅──────── ✧❅✦❅✧────────❅•

✎ _save all the jokes you’re gonna make while i see how much drink i can take, then be my mistake  
_❝Fuck, I screwed up tonight. Fuck.

We were just drinking, It was all fine, she was cracking jokes and I was just playing along, the usual. Until I had one too many. And then I don’t know, I started to remember the first night we drank together… The first night we slept together. And when I looked over at her and it wasn’t you I just… Plus, ‘Samu was talkin’ bout you the other day, saying you’re still good and all that shit. Why'd you even make friends with my brother, huh? Do you think of me when you look at him, though?

God, I’m just a fucking asshole. She’s so fucking perfect to me! So why the fuck aren’t you out of my head yet? Why is it when I woke up earlier with her next to me the first thing I think of is that I wanna talk to you?❞

You remember that night, so clearly. The two of you were drinking your troubles away together when Atsumu’s loving gaze turned into a deathly glare, enough to send shivers down your spine. In all honesty you were wondering if he was going to hit you. Though you have no idea why. Maybe you did something wrong? Even though you knew you didn’t. _That_ was how scary he looked. But he ended up just slamming the mug back down on the table before retreating into the room and banging the door shut.

A few hours later, after you’ve collected yourself and were all cried out, you forced yourself to step into the room, possibly to talk it through with him, seeing how afraid you were earlier. You called out his name in the dark only to find him already curled up on the bed, stirring a little upon hearing you.

You had meekly climbed in next to him and found yourself relieved when he shifted his body to embrace you. Sure, you were happy in the moment, thinking he was just frustrated at something else altogether. But now you see, he was frustrated at _you_. For not being her.

So _that’s_ why he was so persistent about cutting down on his drinking the next day. He had claimed it was for you — and to be fair, he wasn’t completely lying. If he ever told you everything that was on his mind, he was bound to hurt your feelings. And up ’til now, he’d never done that. Because he kept all his frustrations inside, away from you.

•❅──────── ✧❅✦❅✧────────❅•

✎ _i shouldn’t have called, ‘cause we shouldn’t speak  
_❝It was you, wasn’t it? I’m sorry, I couldn’t help myself. I dunno what came over me, really. ‘Samu just went to the toilet for a minute and I just… I knew if I didn’t sneak your number I wouldn’t get another chance. So… you listened to me, didn’t you? God, just hearing you say hello was… nice.

I know you didn’t even speak after that but hey, at least you heard me, right? I just hope you didn’t mute me and leave your phone there… I know you wouldn’t. Even though it was just me reminding you to take care of yourself, I hope you listen to me. I hope you do that. Because if I’m being totally honest, we weren’t perfect together, and it is far from the peace I have in my current relationship but… if you didn’t break up with me, no way in hell would I have let go of you.

Not a chance.❞

Is it possible for you to feel even more dejected? The tears have stopped, because you’re all cried out now. Lucky for that, because there’s one last letter you have yet to read. The one dated yesterday, on the eve of his birthday.

•❅──────── ✧❅✦❅✧────────❅•

✎ _you do make me hard, but she makes me weak_  
❝This is the right thing to do, right? To stay with her and make her happy? I know you’d probably question whether I love her at this point. Thing is, I know the answer.

I do love her.

What I don’t know is… in what way. Or maybe I do know and that I’m in denial. Whatever. But we make each other happy, that must be enough… right?

I just don’t know why you’re the one I can’t stop thinkin’ about. I’m tired, so tired.❞

His last paragraph confuses you, but taking into account everything you just read? There is one thing you do know: this relationship has hit a dead end. Or maybe it wasn’t even a relationship to begin with. Not with him thinking of his ex all the time. Whether or not you remind him of her, she’s always running through his mind, never leaving. And the worst thing is, there’s no one for you to blame, no tangible thing to take your anger out on.

Just the realisation that life is unfair.

•❅──────── ✧❅✦❅✧────────❅•

You glance at the presents and decorations you got for him today for his birthday. You thought of all your plans for tonight. No way any of that is happening now.

Such a waste.

Not only did you have to take them all back, but now you’d have to think of how to move out of here before Atsumu comes back.

You frantically dial a number into your phone. You’d definitely need help with all of this. But also because, maybe, you could afford to give Atsumu one more chance.

This would be the last shot.

“Osamu, could you help me with something?”

•❅──────── ✧❅✦❅✧────────❅•

Atsumu reaches home to find the house completely empty. And not the normal kind of empty. It’s almost completely barren save for his own belongings.

Your shoes that used to scatter around the shoe cabinet are gone. The mirror you brought over from your own apartment had been removed, so is the nail on the wall that had been used to hang it up. He gulps, because he doesn’t know what the fuck is going on.

An uneasy feeling washes over him, and he rushes to the bedroom. He throws open the cabinet, and he feels his heart sinking. Your half of it is completely empty. His eyes widen for a split second when he thinks of the stash of letters he’s kept hidden under the bed. But when he turns around, the wooden board is in place. When he checks inside, the box is exactly where he left it the last time he put it back.

Everything is where it should be. Except for you.

The last he’s heard from you is this morning, when you had texted him about your excitement for tonight. So why is all your stuff gone? Not even a text from you. Atsumu sits on the edge of the bed, head between his hands, trying to fathom just what spurred you to move out. That’s what it is, isn’t it? How else can he explain why all your stuff is gone?

_No, wait,_ that shouldn’t be what he should think about now, right? No, now he should call you and… apologise? Yes, he should. He probably did something wrong without realising, right? Yes, yes, because he can be an absolute blockhead sometimes. That must be it, that must be —

The text tone from his phone snaps him out of his thoughts.

He rushes out to the corridor where he had placed his phone down in a hurry. When he sees your name light up his screen he heaves a sigh of relief. And he gets even more relieved when he actually reads your text.

_Meet me at the park at 7pm, okay? And… you promised me you’d wear your jeans for a special occasion, right? Can you please wear it tonight, babe?_

Atsumu hesitates, but he doesn’t want to risk saying anything wrong, so he hurriedly types a reply.

_Of course, anything you want, babe. See you later, I'm so excited._

It takes everything in him not to ask about your belongings. Maybe you had an unexpected surprise in store. Atsumu knows you. If you were angry, you wouldn’t even bother talking. You’d take time off to yourself. At least he knows he doesn’t have to worry about what he’s done.

Two hours later he finds himself clad up nicely, hair done neatly, heart drumming in his ears as he looks around in the dark of the night. He hasn’t heard from you since you asked to meet him here. He’s beginning to think maybe you stood him up when his phone vibrates.

A text from you.

_In the middle, near the fountain._

Atsumu averts his gaze toward the direction, and he sees a figure moving about, looking uneasy. It’s definitely you, he thinks to himself as he moves closer. You sound different today though, and it’s putting him on edge. Is he supposed to expect an earful from you?

But when the light hits the figure, he stops in his tracks.

“Atsumu?”

There, standing just a few feet in front of him, is the love of his life. But why —

His phone vibrates.

_Happy birthday, ‘Tsumu. I love you._

•❅──────── ✧❅✦❅✧────────❅•

A half hour later you’re in Onigiri Miya, with your _now_ ex-boyfriend’s twin brother serving you up a full meal. You force a smile, thanking him for his hospitality. After all, you needed some place to stay after so hastily moving out of your shared apartment with Atsumu. Osamu had offered, and as much as you didn’t want to impose on him, you really were in no position to refuse. Where else were you going to go? Nobody from your family lives in town and you’re honestly too tired to go around knocking on your friends’ doors and asking if they didn’t mind giving you shelter for an indefinite period of time.

You’re chomping down a mouthful of rice when you hear Osamu sighing, and as you flick your gaze up you catch his exasperated expression. And a roll of his eyes.

“If there’s something you wanna say, say it,” you say through a mouthful of food. You don’t care how un-ladylike you look now. You’re too upset to care about something as trivial as that.

“Stupid.”

You nearly choke on your food. You weren’t expecting that, besides, he was usually more affectionate with you. But before you can offer any retort, he clears his throat and continues.

“Who finds out that their boyfriend is still in love with his ex and then _choose_ to set them up and even offer them _your_ entire birthday plan?” You don’t miss the disapproval in his tone. “Besides, how would ya even know that they’d even be happy this time around?”

Hesitantly, you pull out your phone and wave it at his face. A picture of Atsumu with the love of his life fills the screen, captioned with ‘ _honestly don’t think I could be any happier_ ’.

Osamu sighs, giving in. He knows chiding you about it wouldn’t do any good right now anyway.

Instead, he settles for just a “yer amazing, ya know that?”

“Whatever.” You roll your eyes at his sarcasm as your gaze falls upon the food cooked by the man himself, but mind elsewhere.

Except it wasn’t sarcasm. And just as you missed all of the cues that pointed to Atsumu still being infatuated with someone else, you miss the hint of love in Osamu’s eyes as he gazes down at you, wondering when, if ever, you’ll feel for him the way you feel for his brother.


End file.
